The verb to lie

Lie /laɪ/ is two different verbs. (1) To be in a flat position, for example on a bed (no object, irregular): lie → lay → lain. (2) To say something that is not true (regular): lie → lied → lied. Same base form, different past forms.

Lie has no object: you lie on the bed yourself. Lie → lay → lain. Lay has an object: you put something down. Lay → laid → laid. I lie on the sofa. I lay the book on the table. It is one of the most famous traps in English, because the Past Simple of lie is lay!

Spelling rule: in verbs that end in -ie, ie becomes y before -ing. Lie → lying. Die → dying. Tie → tying. This avoids three vowels in a row.

A white lie is a small, harmless lie that you tell to be kind, so that you don't hurt someone's feelings. I love your hair! can be a white lie. People use them a lot in social life.

Lie low is an idiom: to stay quiet and hidden for a while, so that people don't notice you. After the scandal, he's lying low.